Amplifier and oscilloscope

Abstract

The amplifier comprises a transconductance amplifier module (100), a feedforward transconductance module (200), and a gain control module (300). The transconductance amplifier module (100) is configured to receive an input signal pair (VIP, VIN) at a pair of input control terminals (101P, 101N), convert the input signal pair (VIP, VIN) into an output current pair (IOP, ION) and output the same. The feedforward transconductance module (200) comprises a first feedforward control terminal pair (201P, 201N) that receives the input signal pair (VIP, VIN) and outputs a feedforward current pair. The gain control module (300) has a first output terminal (302P) and a second output terminal (303P) that respectively convert the input signal pair (VIP, VIN) into an output current pair (IOP, ION). inverse Phase output current and just A first differential pair (301) configured to compensate for a phase output current, a first output terminal (302N) and a second output terminal (303N) each being one of the output current pairs. inverse Phase output current and just and a second differential pair (302) configured to compensate for the phase output current.

Description

[Technical Field]

[0001] This application claims priority from a Chinese patent application bearing application number 202410199737.4, filed with the China Patent Office on February 23, 2024, the entire contents of which are incorporated herein by reference.

[0002] This application relates to the technical field of circuits, for example amplifiers and oscilloscopes. [Background technology]

[0003] High-bandwidth amplifiers are typically used in systems that require high-frequency signal processing, such as oscilloscope analog front-ends and probe analog front-ends. In these circuits, high-frequency signals can maintain high gain and frequency response through high-bandwidth amplifiers. The high-frequency response of high-bandwidth amplifiers in the related art is significantly affected by chip processes and printed wiring board processes. Due to such process variations, the frequency responses of amplifiers from different lots may not match, which may not meet user needs. Summary of the Invention

[0004] The present application provides an amplifier and an oscilloscope to overcome process variations.

[0005] According to one aspect of the present application, a transconductance amplifier module having a pair of input control terminals to which a pair of input signals are input, the transconductance amplifier module being configured to convert the pair of input signals into a pair of output currents and output the output currents; a feedforward transconductance module including a first pair of feedforward control terminals that receives the pair of input signals and outputs a pair of feedforward currents including a positive-phase feedforward current and a negative-phase feedforward current; a gain control module comprising a first differential pair and a second differential pair; The input terminal of the first differential pair and the input terminal of the second differential pair are a feedforward current input terminal pair of the gain control module, and the first differential pair receives the positive-phase feedforward current at its input terminal and outputs a first positive-phase compensation current at its first output terminal. reverse a second output terminal configured to output a second positive-phase compensation current; Positive The second differential pair is configured to receive the negative-phase feedforward current at its input end and output a first negative-phase compensation current at its first output end, and the second differential pair is configured to compensate for the negative-phase output current of the output current pair. reverse a second output terminal configured to output a second anti-phase compensation current; Positive An amplifier configured to compensate for the phase output current is provided.

[0006] According to another aspect of the present application, there is provided an oscilloscope comprising: a front-end module having an attenuation unit and an amplifier according to any one of the embodiments of the present application, the input end of which is connected to the attenuation unit; a sampling module; an input module; a control processing module; a display module; and a storage module.

[0007] According to another aspect of the present application, there is provided an oscilloscope probe including: a probe input terminal; a probe input resistor; a probe input capacitor; an amplifier according to any one of the embodiments of the present application, the amplifier having an input terminal connected to the probe input resistor and the probe input capacitor, respectively; and a probe output terminal. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a structural schematic diagram of one amplifier according to an embodiment of the present application. [Figure 2] FIG. 10 is a circuit schematic diagram of another amplifier according to an embodiment of the present application. [Figure 3] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 4]FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 5] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 6] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 7] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 8] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 9] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 10] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 11] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 12] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 13] FIG. 10 is a circuit schematic diagram of yet another amplifier according to an embodiment of the present application. [Figure 14] 1 is a structural schematic diagram of an oscilloscope according to an embodiment of the present application; [Figure 15] FIG. 2 is a structural schematic diagram of yet another oscilloscope according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0009] It should be noted that the terms "first," "second," etc. in the specification, claims, and drawings of this application are not necessarily used to describe a particular order or sequence, but are merely used to distinguish between similar objects. Such used data may be substituted where appropriate, and it should be understood that the embodiments of this application described herein may be practiced in orders other than those illustrated or described herein. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions; for example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those explicitly recited steps or units, but may include other steps or units that are not explicitly recited or that are inherent to the process, method, product, or apparatus.

[0010] FIG. 1 is a structural schematic diagram of an amplifier according to an embodiment of the present application. Referring to FIG. 1, the amplifier includes a transconductance amplifier module 100, a feedforward transconductance module 200, and a gain control module 300.

[0011] The transconductance amplifier module 100 includes a pair of input control terminals (including a terminal 101P and a terminal 101N) to which a pair of input signals (including a positive-phase input signal VIP and a negative-phase input signal VIN) are input. The transconductance amplifier module 100 is configured to convert the pair of input signals (including the positive-phase input signal VIP and the negative-phase input signal VIN) into a pair of output currents (including a positive-phase output current IOP and a negative-phase output current ION) and output them.

[0012] The feedforward transconductance module 200 includes a first pair of feedforward control terminals (including terminals 201P and 201N) that receive a pair of input signals (including a positive-phase input signal VIP and a negative-phase input signal VIN). The feedforward transconductance module 200 is configured to generate a pair of feedforward currents (including a positive-phase feedforward current and a negative-phase feedforward current) based on the pair of input signals.

[0013] The gain control module 300 includes a first differential pair 301 and a second differential pair 302. The input terminals of the first differential pair 301 and the second differential pair 302 are connected to a feedforward current input terminal pair (including a terminal 301P and a terminal 301N) of the gain control module. A positive-phase feedforward current is input to the input terminal of the first differential pair 301. A first output terminal 302P of the first differential pair 301 outputs a first positive-phase compensation current. reverse The second output terminal 303P of the first differential pair 301 outputs a second positive-phase compensation current, and the second output terminal 303P of the first differential pair 301 outputs a second positive-phase compensation current. Positive The second differential pair 302 is configured to compensate for the phase output current, and the input terminal of the second differential pair 302 receives a negative-phase feedforward current, and the first output terminal 302N of the second differential pair 302 outputs a first negative-phase compensation current, and the second differential pair 302 is configured to compensate for the phase output current of the output current pair. reverse The second output terminal 303N of the second differential pair 302 is configured to compensate for the phase output current, and the second output terminal 303N of the second differential pair 302 outputs a second anti-phase compensation current, and the second output terminal 303N of the output current pair Positive The phase output current is configured to be compensated.

[0014] The feedforward current input pair (including terminals 301P and 301N) receives the feedforward current pair generated by the feedforward transconductance module 200. The currents output from the first output terminal 302P and the second output terminal 303P of the first differential pair 301 are positive-phase compensation currents generated based on the positive-phase input signal VIP, which are used to compensate for both the positive-phase output current IOP and the negative-phase output current ION. Similarly, the currents output from the first output terminal 302N and the second output terminal 303N of the second differential pair 302 are negative-phase compensation currents generated based on the negative-phase input signal VIN. The negative-phase compensation currents are used to compensate for both the negative-phase output current ION and the positive-phase output current IOP.

[0015] In other words, the current output from the second output terminal 303P of the first differential pair 301 is a positive-phase compensation current generated based on the positive-phase input signal VIP, and the current output from the first output terminal 302N of the second differential pair 302 is a negative-phase compensation current generated based on the negative-phase input signal VIN. The second output terminal 303P of the first differential pair 301 corresponds to the positive-phase output current IOP, and the first output terminal 302N of the second differential pair 302 corresponds to the negative-phase output current ION. That is, the positive-phase compensation current compensates for the positive-phase output current IOP of the transconductance amplifier module 100, and the negative-phase compensation current compensates for the negative-phase output current ION of the transconductance amplifier module 100. The compensation currents output from the second output terminal 303P of the first differential pair 301 and the first output terminal 302N of the second differential pair 302 constitute a first group of compensation current pairs, which are output superimposed with the output current pairs in a corresponding manner.

[0016] The current output from the first output terminal 302P of the first differential pair 301 is a positive-phase compensation current generated based on the positive-phase input signal VIP, and the current output from the second output terminal 303N of the second differential pair 302 is a negative-phase compensation current generated based on the negative-phase input signal VIN. The first output terminal 302P of the first differential pair 301 corresponds to the negative-phase output current ION, and the second output terminal 303N of the second differential pair 302 corresponds to the positive-phase output current IOP. That is, the positive-phase compensation current compensates for the negative-phase output current ION of the transconductance amplifier module 100, and the negative-phase compensation current compensates for the positive-phase output current IOP of the transconductance amplifier module 100. The compensation currents output from the first output terminal 302P of the first differential pair 301 and the second output terminal 303N of the second differential pair 302 constitute a second group of compensation current pairs, which are output alternately superimposed with the output current pairs.

[0017] For example, the amplifier operates as follows: an input signal pair (including a positive-phase input signal VIP and a negative-phase input signal VIN) passes through the transconductance amplifier module 100 and is converted into an output current pair (including a positive-phase output current IOP and a negative-phase output current ION). The feedforward transconductance module 200 generates a feedforward current pair based on the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN). The gain control module 300 generates two groups of compensation current pairs based on the feedforward current pair, one group of compensation current pairs being superimposed on the amplifier output in a corresponding manner, and the other group of compensation current pairs being superimposed on the amplifier output in an alternating manner, thereby achieving compensation for the frequency response of the original output current. The frequency and gain of the two groups of compensation current pairs are controlled by the gain control module 300. Depending on the frequency response characteristics of different batches of amplifiers, the frequency response can be lowered when the frequency response is high and increased when the frequency response is low until the frequency responses are equal.

[0018] As described above, the technical aspect of this embodiment is such that the transconductance amplifier module 100 converts an input signal pair (including a positive-phase input signal VIP and a negative-phase input signal VIN) into an output current pair (including a positive-phase output current IOP and a negative-phase output current ION), and the gain control module 300 generates two groups of compensation current pairs based on the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN), and outputs the two groups of compensation current pairs by superimposing them on the output current pairs in a corresponding manner and an alternating manner, thereby eliminating the influence of process variations on the frequency response.

[0019] 2 is a circuit schematic diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 2, a transconductance amplifier module 100 includes a first current source unit 101, a zeroth transistor Q0, and a first transistor Q1. The first current source unit 101 includes a first node pair, which includes a first node 102P and a second node 102N. The first current source unit 101 is electrically connected to a first power supply voltage (e.g., a ground voltage GND).

[0020] The control terminal of the zeroth transistor Q0 and the control terminal of the first transistor Q1 are connected to a pair of input control terminals (including a terminal 101P and a terminal 101N) of the transconductance amplifier module 100. The first terminal of the zeroth transistor Q0 is electrically connected to a first connection point 102P of the first current source unit 101, and the first terminal of the first transistor Q1 is electrically connected to a second connection point 102N of the first current source unit 101. The second terminal of the zeroth transistor Q0 and the second terminal of the first transistor Q1 output a pair of output currents (including a positive-phase output current IOP and a negative-phase output current ION) of the transconductance amplifier module 100.

[0021] For example, the working principle of the transconductance amplifier module 100 is that a positive-phase input signal VIP is converted into a positive-phase output current IOP via the zeroth transistor Q0, and a negative-phase input signal VIN is converted into a negative-phase output current ION via the first transistor Q1, and the gain of the output current pair is controlled by the first current source unit 101.

[0022] 3 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 3, in one embodiment, the first current source unit 101 includes a first current source 1011, a current input terminal of the first current source 1011 is electrically connected to the first connection point 102P and the second connection point 102N of the first current source unit 101, and a current output terminal of the first current source 1011 is electrically connected to a first power supply voltage.

[0023] By controlling the current of the first current source 1011, the transconductance of the transistor in the transconductance amplifier module 100 is controlled, thereby controlling the magnitude of the gain of the output current. This makes it easier to implement, does not increase the circuit area, and is advantageous for cost control.

[0024] 4 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 4, in another embodiment, the first current source unit 102 includes a second current source 1012, a first resistor unit R1, and a second resistor unit R2, the first resistor unit R1 is connected in series between the current input terminal of the second current source 1012 and the first connection point 102P of the first current source unit 101, the second resistor unit R2 is connected in series between the current input terminal of the second current source 1012 and the second connection point 102N of the first current source unit 101, and the current output terminal of the second current source 1012 is electrically connected to a first power supply voltage.

[0025] By controlling the current of the second current source 1012, the resistance of the first resistor unit R1, and the resistance of the second resistor unit R2, the equivalent transconductance of the transconductance amplifier module 100 can be controlled, thereby controlling the magnitude of its output current gain. In this way, compared to providing only a single current source, by adding a resistor unit to the emitter of the transistor in the transconductance amplifier module 100, the output current gain is jointly controlled by the current of the current source and the resistance of the resistor unit, thereby increasing the adjustability of the output current gain.

[0026] 5 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 5, in another embodiment, the first current source unit 103 includes a third current source 1013, a fourth current source 1014, and a third resistor unit R3. The current input terminal of the third current source 1013 is electrically connected to the first connection point 102P of the first current source unit 101, and the current input terminal of the fourth current source 1014 is electrically connected to the second connection point 102N of the first current source unit 101. A third resistor unit R3 is further connected between the current input terminal of the third current source 1013 and the current input terminal of the fourth current source 1014. The current output terminal of the third current source 1013 and the current output terminal of the fourth current source 1014 are both electrically connected to the first power supply voltage.

[0027] By controlling the currents of the third current source 1013 and the fourth current source 1014 and the resistance value of the third resistor unit R3, the equivalent transconductance of the transconductance amplifier module 100 can be controlled, thereby controlling the magnitude of the gain of its output current. In this way, compared to a structure in which a single current source is connected to two resistor units, when a single resistor unit is provided, there is no need to consider resistance matching issues, which is advantageous for stably adjusting the gain of the output current.

[0028] 1 to 5, the gain control module 300 further includes a gain control unit 303, which includes a second pair of nodes (including node 305P and node 305N), the second pair of nodes (including node 305P and node 305N) of the gain control unit 303 being electrically connected to a control end of the first differential pair 301, and the second pair of nodes (including node 305P and node 305N) being electrically connected to a control end of the second differential pair 302. The second pair of nodes (including node 305P and node 305N) of the gain control unit 303 is configured to output a second control current pair and perform gain control on the output currents of the first differential pair 301 and the second differential pair 302.

[0029] In this embodiment, the first differential pair 301, the second differential pair 302 and the gain control unit 303 control the frequency and gain of the output current of the feedforward transconductance module 200, which is advantageous in further eliminating process variations and compensating for frequency response.

[0030] 6 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 6, a first differential pair 301 includes a second transistor Q2 and a third transistor Q3, and a first terminal of the second transistor Q2 and a first terminal of the third transistor Q3 are electrically connected to an input terminal (i.e., a terminal 301P) of the first differential pair 301. The control terminal of the second transistor Q2 and the control terminal of the fifth transistor Q5 are electrically connected to each other; The control terminal of the second transistor Q2 and the control terminal of the third transistor Q3 are connected to the control terminal pair of the first differential pair 301, the second terminal of the second transistor Q2 is connected to the first output terminal 302P of the first differential pair 301 to output a first positive phase compensation current, and the second terminal of the third transistor Q3 is connected to the second output terminal 303P of the first differential pair 301 to output a second positive phase compensation current.

[0031] Continuing to refer to FIG. 6, the second differential pair 302 includes a fourth transistor Q4 and a fifth transistor Q5, a first terminal of the fourth transistor Q4 and a first terminal of the fifth transistor Q5 are electrically connected to an input terminal (terminal 301N) of the second differential pair 302, The control terminal of the third transistor Q3 and the control terminal of the fourth transistor Q4 are electrically connected to each other,The control terminal of the fourth transistor Q4 and the control terminal of the fifth transistor Q5 are connected to the control terminal pair of the second differential pair 302, the second terminal of the fourth transistor Q4 is connected to the first output terminal 302N of the second differential pair 302 to output a first negative-phase compensation current, and the second terminal of the fifth transistor Q5 is connected to the second output terminal 303N of the second differential pair 302 to output a second negative-phase compensation current.

[0032] Among them, the second output terminal 303P of the first differential pair 301 and the second output terminal 303N of the second differential pair 302 output the compensation current pairs of the second group, and the first output terminal 302P of the first differential pair 301 and the first output terminal 302N of the second differential pair 302 output the compensation current pairs of the first group.

[0033] For example, the first differential pair 301 and the second differential pair 302 operate as follows: a positive-phase compensation current passes through the second transistor Q2 to generate a first positive-phase compensation current, and simultaneously passes through the third transistor Q3 to generate a second positive-phase compensation current; a negative-phase compensation current passes through the fourth transistor Q4 to generate a first negative-phase compensation current, and simultaneously passes through the fifth transistor Q5 to generate a second negative-phase compensation current; the second positive-phase compensation current and the first negative-phase compensation current constitute a first compensation current pair, and the first positive-phase compensation current and the second negative-phase compensation current constitute a second compensation current pair.

[0034] In this embodiment, the first differential pair 301 is provided with the second transistor Q2 and the third transistor Q3, and the second differential pair 302 is provided with the fourth transistor Q4 and the fifth transistor Q5. This allows the first compensation current pair and the second compensation current pair to be generated based on the input signal and superimposed on the output current pair, which is advantageous in further eliminating process variations and compensating for frequency response.

[0035] 7 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 7, a feedforward transconductance module 200 includes a sixth transistor Q6, a seventh transistor Q7, and a second current source unit 202. The second current source unit 202 includes a third node pair (including a node 202P and a node 202N).

[0036] The control terminal of the sixth transistor Q6 and the control terminal of the seventh transistor Q7 are respectively connected to the first pair of feedforward control terminals (including terminal 201P and terminal 201N) of the feedforward transconductance module 200. The first terminal of the sixth transistor Q6 and the first terminal of the seventh transistor Q7 are respectively electrically connected to the third pair of connection points (including third connection point 202P and fourth connection point 202N) of the second current source unit 202. The second terminal of the sixth transistor Q6 and the second terminal of the seventh transistor Q7 are respectively electrically connected to the pair of feedforward current input terminals (including terminal 301P and terminal 301N) of the gain control module 300. Exemplarily, the second terminal of the sixth transistor Q6 is electrically connected to the first terminal of the second transistor Q2 and the first terminal of the third transistor Q3, and the second terminal of the seventh transistor Q7 is electrically connected to the first terminal of the fourth transistor Q4 and the first terminal of the fifth transistor Q5.

[0037] Wherein, the third pair of nodes (including the node 202P and the node 202N) of the second current source unit 202 is configured to output the first control current pair and perform frequency control on the output current of the feedforward transconductance module 200.

[0038] For example, the working principle of the feedforward transconductance module 200 is that, under the control of the second current source unit 202, the positive-phase input signal VIP is converted into a positive-phase compensation current through the sixth transistor Q6, and the negative-phase input signal VIN is converted into a negative-phase compensation current through the seventh transistor Q7.

[0039] The positive-phase compensation current passes through the second transistor Q2 to generate a first positive-phase compensation current, and simultaneously passes through the third transistor Q3 to generate a second positive-phase compensation current. The negative-phase compensation current passes through the fourth transistor Q4 to generate a first negative-phase compensation current, and simultaneously passes through the fifth transistor Q5 to generate a second negative-phase compensation current. The second positive-phase compensation current and the first negative-phase compensation current form a first compensation current pair, and the first positive-phase compensation current and the second negative-phase compensation current form a second compensation current pair.

[0040] As can be seen, the feedforward transconductance module 200 generates currents related to the frequency of the output current of the feedforward transconductance module 200, i.e., a first control current pair, via the second current source unit 202, to control the frequency of the output current of the feedforward transconductance module 200. The gain control module 300 generates currents related to the gain of the output current of the feedforward transconductance module 200, i.e., a second control current pair, to control the gain of the output current of the feedforward transconductance module 200.

[0041] In this embodiment, the feedforward transconductance module 200 includes a sixth transistor Q6, a seventh transistor Q7, and a second current source unit 202, which generate positive and negative compensation currents whose frequencies are controllable based on the input signal. These currents are then superimposed on the output current pair by the gain control module 300, which is advantageous in further eliminating process variations and compensating for frequency response.

[0042] 8 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 8, the third connection point pair of the second current source unit 202 includes a third connection point 202P and a fourth connection point 202N. The second current source unit 202 includes a fifth current source 2022, a sixth current source 2023, and a current control sub-unit 2021.

[0043] The current input terminal of the fifth current source 2022 is connected to the third connection point 202P of the second current source unit 202, and the current output terminal of the fifth current source 2022 is electrically connected to a fifth power supply voltage (for example, the ground voltage GND).

[0044] The current input terminal of the sixth current source 2023 is connected to the fourth connection point 202N of the second current source unit 202, and the current output terminal of the sixth current source 2023 is electrically connected to a sixth power supply voltage (for example, the ground voltage GND).

[0045] The current control sub-unit 2021 is connected in series between the current input terminal of the fifth current source 2022 and the current input terminal of the sixth current source 2023 .

[0046] By controlling the currents of the fifth current source 2022 and the sixth current source 2023, the transconductance of the sixth transistor Q6 and the seventh transistor Q7 is controlled to control the magnitude of the gain of the output current, and the frequency of the output current is controlled by the current control sub-unit 2021. In this way, the circuit structure is simple and easy to implement.

[0047] 9 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 9, in one embodiment, the current control subunit 2021 includes a fourth resistor unit R4 and a first capacitor unit C1, a first end of the fourth resistor unit R4 is connected to a first end of the current control subunit 2021, a second end of the fourth resistor unit R4 is electrically connected to a first end of the first capacitor unit C1, and a second end of the first capacitor unit C1 is connected to a second end of the current control subunit 2021.

[0048] Since a frequency-related current is generated in the fourth resistor unit R4 and the first capacitor unit C1, the frequency and gain of the compensation current are determined by the resistance value of the fourth resistor unit R4 and the capacitance value of the first capacitor unit C1, making the circuit structure simple and easy to implement.

[0049] 10 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 10, in another embodiment, the current control subunit 2021 includes a second capacitor unit C2, a first end of the second capacitor unit C2 is connected to the first end of the current control subunit 2021, and a second end of the second capacitor unit C2 is connected to the second end of the current control subunit 2021.

[0050] Since a current related to the frequency is generated across the second capacitor unit C2, the frequency and gain of the compensation current are determined by the capacitance value of the second capacitor unit C2. This is applicable to circuits that compensate for high-frequency currents, and is advantageous in terms of saving circuit area and reducing costs compared to a configuration in which a resistor and a capacitor are connected in series.

[0051] 11 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 11, in another embodiment, the current control sub-unit 2021 includes a fifth resistor unit R5, a first end of the fifth resistor unit R5 is connected to a first end of the current control sub-unit 2021, and a second end of the fifth resistor unit R5 is connected to a second end of the current control sub-unit 2021.

[0052] Since the fifth resistor unit R5 generates a frequency-related current, the gain of the compensation current is determined by the resistance value of the fifth resistor unit R5, so that the compensation current has a full frequency band, i.e., the compensation current can compensate for both DC signals and AC signals of different frequencies, which is more advantageous in eliminating process variations and compensating for frequency response.

[0053] 12 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 12, the gain control unit 303 further includes a first adjustable current source I0, a second adjustable current source I1, an eighth transistor Q8, and a ninth transistor Q9.

[0054] The first terminal of the eighth transistor Q8 and the first terminal of the ninth transistor Q9 are electrically connected to the current input terminal of the first adjustable current source I0 and the current input terminal of the second adjustable current source I1, respectively, and the control terminal of the eighth transistor Q8, the control terminal of the ninth transistor Q9, the second terminal of the eighth transistor Q8, and the second terminal of the ninth transistor Q9 are electrically connected to the second power supply voltage Vb.

[0055] The current input terminal of the first adjustable current source I0 and the current input terminal of the second adjustable current source I1 are connected to a second pair of nodes (including a node 305P and a node 305N) of the gain control unit 303. The current output terminal of the first adjustable current source I0 is electrically connected to a third power supply voltage (e.g., ground voltage GND). The current output terminal of the second adjustable current source I1 is electrically connected to a fourth power supply voltage (e.g., ground voltage GND).

[0056] For example, if the transistor is a triode, the control end of the transistor is the base of the triode, the first end of the transistor is the emitter of the triode, and the second end of the transistor is the collector of the triode. The working principle of the gain control unit 303 is to control the gain of the currents output from the first differential pair and the second differential pair by controlling the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4, and the fifth transistor Q5. When the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4, and the fifth transistor Q5 are equal, the first positive-phase compensation current output from the second transistor Q2 flows to the negative-phase output terminal, the second positive-phase compensation current output from the third transistor Q3 flows to the in-phase output terminal, the first negative-phase compensation current output from the fourth transistor Q4 flows to the negative-phase output terminal, and the second negative-phase compensation current output from the fifth transistor Q5 flows to the in-phase output terminal. In this case, the compensation currents flowing through the in-phase output terminal and the anti-phase output terminal cancel each other out, and do not affect the gain of the output current.

[0057] By adjusting the gain control unit 303, the current of the first adjustable current source I0 is increased and the current of the second adjustable current source I1 is decreased, thereby decreasing the emitter voltage of the eighth transistor Q8 and the emitter voltage of the ninth transistor Q9. This increases the base voltages of the third transistor Q3 and the fourth transistor Q4, increasing the second positive-phase compensation current flowing to the in-phase output and the first negative-phase compensation current flowing to the negative-phase output. The base voltages of the second transistor Q2 and the fifth transistor Q5 are decreased, decreasing the second negative-phase compensation current flowing to the in-phase output and the first positive-phase compensation current flowing to the negative-phase output. Finally, the effective currents flowing to the in-phase output and the negative-phase output increase, increasing the overall current gain. For example, when the frequency response at a frequency point is low, the gain of the compensation current needs to be increased to compensate for the frequency response.

[0058] By adjusting the gain control unit 303, when the current of the first adjustable current source I0 is decreased and the current of the second adjustable current source I1 is increased, the emitter voltage of the eighth transistor Q8 increases and the emitter voltage of the ninth transistor Q9 decreases. This decreases the base voltages of the third transistor Q3 and the fourth transistor Q4, reducing the second positive-phase compensation current flowing to the in-phase output and the first negative-phase compensation current flowing to the negative-phase output. The base voltages of the second transistor Q2 and the fifth transistor Q5 increase, increasing the second negative-phase compensation current flowing to the in-phase output and the first positive-phase compensation current flowing to the negative-phase output. Finally, the effective currents flowing to the in-phase output and the negative-phase output are reduced, resulting in a smaller overall current gain. For example, when the frequency response of a frequency point is high, the gain of the compensation current needs to be reduced to compensate for the frequency response.

[0059] The gain control unit 303 has multiple installation methods, and the alternating compensation unit (Comprising a first differential pair 301 and a second differential pair 302)The purpose of this is to control the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4 and the fifth transistor Q5 in the MOSFETs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55, 56, 57,

[0060] In this embodiment, the gain control unit 303 is provided with a first adjustable current source I0, a second adjustable current source I1, an eighth transistor Q8, and a ninth transistor Q9, which controls the base voltage of the transistor in the alternating compensation unit connected thereto, thereby controlling the gain of the output current of the alternating compensation unit and achieving frequency response compensation. This has a simple circuit structure, is easy to implement, and is favorable for accurately adjusting the current gain.

[0061] 13 is a circuit diagram of another amplifier according to an embodiment of the present application. Referring to FIG. 13, the amplifier further includes a first current buffer module 400; The first current buffer module 400 is connected in series between the transconductance amplifier module 100 and the output terminal of the amplifier. The first current buffer module 400 has a first buffer control terminal pair (including a terminal 401P and a terminal 401N), and the first buffer control terminal pair receives a reference voltage V1.

[0062] 13, the first current buffer module 400 includes a tenth transistor Q10 and an eleventh transistor Q11, and the control terminal of the tenth transistor Q10 and the control terminal of the eleventh transistor Q11 receive a reference voltage V1. The first terminal of the tenth transistor Q10 and the first terminal of the eleventh transistor Q11 receive the output current pair of the transconductance amplifier module 100. The second terminal of the tenth transistor Q10 and the second terminal of the eleventh transistor Q11 output the first buffer current pair (including terminals 402P and 402N).

[0063] The first buffer current pair includes a positive-phase buffer current and a negative-phase buffer current. The positive-phase output current of the transconductance amplifier module 100 is converted into a positive-phase buffer current through the tenth transistor Q10 and flows to the in-phase output terminal. The negative-phase output current of the transconductance amplifier module 100 is converted into a negative-phase buffer current through the eleventh transistor Q11 and flows to the negative-phase output terminal.

[0064] In this embodiment, a first current buffer module 400 is provided, and the transistors provided therein are used to buffer the output current pair of the transconductance amplifier module 100, thereby improving the stability of the circuit.

[0065] In the above embodiments, the transistors are triodes, but the present invention is not limited to this, and in other embodiments, the transistors may be MOS transistors or the like.

[0066] An embodiment of the present application further provides an oscilloscope, which includes the amplifier according to any of the above embodiments. The oscilloscope according to this embodiment has the beneficial effects of the amplifier according to any of the above embodiments, and the description thereof will not be repeated here.

[0067] 14 is a structural schematic diagram of an oscilloscope according to an embodiment of the present application. Referring to FIG. 14, the oscilloscope includes a front-end module 1, a sampling module 2, an input module 3, a control processing module 4, a display module 5, and a storage module 6. The front-end module 1 includes an attenuation unit 11 and an amplifier 12. The input terminal of the amplifier 12 is connected to the attenuation unit 11.

[0068] 15 is a structural schematic diagram of another oscilloscope according to an embodiment of the present application. Referring to FIG. 15, the oscilloscope includes an oscilloscope probe 7 and an oscilloscope input resistor R in It is equipped with:

[0069] An embodiment of the present application further provides an oscilloscope probe, which includes the amplifier according to any of the above embodiments. The oscilloscope probe according to this embodiment has the beneficial effects of the amplifier according to any of the above embodiments, and the description thereof will not be repeated here.

[0070] Referring to FIG. 15, the oscilloscope probe 7 includes a probe input terminal 72 and a probe input resistor R probe and the probe input capacitor C probe , an amplifier 71, and a probe output terminal 73. The input terminal of the amplifier 71 is connected to a probe input resistor R probe and probe input capacitor C probe The probe output 73 is connected to the oscilloscope input resistor R in is connected to.

[0071] It should be understood that various types of flows shown above can be used, and steps can be rearranged, added, or deleted. For example, the steps described herein can be performed in parallel, sequentially, or in a different order, and this specification does not limit the scope of the present invention as long as the desired results of the technical aspects of the present invention are achieved.

Claims

1. a transconductance amplifier module having a pair of input control terminals to which a pair of input signals are input, the transconductance amplifier module being configured to convert the pair of input signals into a pair of output currents and output the output currents; a feedforward transconductance module including a first pair of feedforward control terminals that receives the pair of input signals and outputs a pair of feedforward currents including a positive-phase feedforward current and a negative-phase feedforward current; a gain control module comprising a first differential pair and a second differential pair; an input terminal of the first differential pair and an input terminal of the second differential pair are configured as a feedforward current input terminal pair of the gain control module, the first differential pair having an input terminal receiving the positive-phase feedforward current, a first output terminal outputting a first positive-phase compensation current to compensate for the positive-phase output current of the output current pair, and a second output terminal outputting a second positive-phase compensation current to compensate for the negative-phase output current of the output current pair; the second differential pair having an input terminal receiving the negative-phase feedforward current, a first output terminal outputting a first negative-phase compensation current to compensate for the positive-phase output current of the output current pair, and a second output terminal outputting a second negative-phase compensation current to compensate for the negative-phase output current of the output current pair; Amplifier.

2. The transconductance amplifier module includes a first connection point pair including a first connection point and a second connection point, and includes a first current source unit electrically connected to a first power supply voltage, a zeroth transistor, and a first transistor; a control end of the zero transistor and a control end of the first transistor are connected to an input control end pair of the transconductance amplifier module, a first end of the zero transistor is electrically connected to a first connection point of the first current source unit, a first end of the first transistor is electrically connected to a second connection point of the first current source unit, and a second end of the zero transistor and a second end of the first transistor output an output current pair of the transconductance amplifier module; 10. The amplifier of claim 1.

3. The first current source unit includes a first current source having a current input terminal electrically connected to a first connection point and a second connection point of the first current source unit and a current output terminal electrically connected to a first power supply voltage; the first current source unit comprises a second current source, a first resistor unit and a second resistor unit, the second current source has the first resistor unit connected in series between a current input terminal and a first connection point of the first current source unit, the second resistor unit connected in series between a current input terminal and a second connection point of the first current source unit, and a current output terminal electrically connected to a first power supply voltage; the first current source unit comprises a third current source, a fourth current source, and a third resistor unit, a current input terminal of the third current source electrically connected to a first connection point of the first current source unit, a current input terminal of the fourth current source electrically connected to a second connection point of the first current source unit, the third resistor unit is further connected between the current input terminal of the third current source and the current input terminal of the fourth current source, and a current output terminal of the third current source and a current output terminal of the fourth current source electrically connected to a first power supply voltage, 3. The amplifier of claim 2.

4. The gain control module: a gain control unit including a second pair of connection points electrically connected to the control end pair of the first differential pair and electrically connected to the control end pair of the second differential pair, the second pair of connection points configured to output a second pair of control currents and to perform gain control on the output currents of the first differential pair and the second differential pair; 10. The amplifier of claim 1.

5. the first differential pair includes a second transistor and a third transistor; a first terminal of the second transistor and a first terminal of the third transistor are electrically connected to each other and serve as an input terminal of the first differential pair; a control end of the second transistor and a control end of the third transistor are electrically connected to form a control end pair of the first differential pair; a second terminal of the second transistor is connected to a first output terminal of the first differential pair and outputs the first positive phase compensation current; a second terminal of the third transistor is connected to a second output terminal of the first differential pair and outputs the second positive phase compensation current; and / or the second differential pair comprises a fourth transistor and a fifth transistor; a first terminal of the fourth transistor and a first terminal of the fifth transistor are electrically connected to each other and serve as an input terminal of the second differential pair; a control end of the fourth transistor and a control end of the fifth transistor are electrically connected to form a control end pair of the second differential pair; a second terminal of the fourth transistor is connected to a first output terminal of the second differential pair and outputs the first negative-phase compensation current; and a second terminal of the fifth transistor is connected to a second output terminal of the second differential pair and outputs the second negative-phase compensation current.

5. The amplifier of claim 4.

6. the feedforward transconductance module comprises a sixth transistor, a seventh transistor, and a second current source unit comprising a third node pair; the control end of the sixth transistor and the control end of the seventh transistor are connected to a first pair of feedforward control ends of the feedforward transconductance module, the first end of the sixth transistor and the first end of the seventh transistor are electrically connected to a third pair of connection ends of the second current source unit, respectively; and the second end of the sixth transistor and the second end of the seventh transistor are electrically connected to a pair of feedforward current input ends of the gain control module, respectively; a third pair of nodes of the second current source unit configured to output a first pair of control currents and to perform frequency control on the output current of the feedforward transconductance module; 10. The amplifier of claim 1.

7. the third connection point pair of the second current source unit includes a third connection point and a fourth connection point; The second current source unit: a fifth current source, the current input terminal of which is connected to the third connection point of the second current source unit and the current output terminal of which is electrically connected to a fifth power supply voltage; a sixth current source, the current input terminal of which is connected to the fourth connection point of the second current source unit and the current output terminal of which is electrically connected to a sixth power supply voltage; a current control subunit connected in series between the current input terminal of the fifth current source and the current input terminal of a sixth current source; 7. The amplifier of claim 6.

8. the current control subunit comprises a fourth resistor unit and a first capacitor unit, a first end of the fourth resistor unit being connected to the first end of the current control subunit and a second end of the fourth resistor unit being electrically connected to the first end of the first capacitor unit, and a second end of the first capacitor unit being connected to the second end of the current control subunit; the current control subunit includes a second capacitor unit having a first end connected to the first end of the current control subunit and a second end connected to the second end of the current control subunit; the current control subunit includes a fifth resistor unit having a first end connected to the first end of the current control subunit and a second end connected to the second end of the current control subunit; 8. The amplifier of claim 7.

9. the gain control unit comprises a first adjustable current source, a second adjustable current source, an eighth transistor, and a ninth transistor; a first end of the eighth transistor and a first end of the ninth transistor are electrically connected to a current input end of the first adjustable current source and a current input end of the second adjustable current source, respectively; a control end of the eighth transistor, a control end of the ninth transistor, a second end of the eighth transistor, and a second end of the ninth transistor are electrically connected to a second power supply voltage; the current input terminal of the first adjustable current source and the current input terminal of the second adjustable current source are connected to a second connection point pair of the gain control unit, the current output terminal of the first adjustable current source is electrically connected to a third power supply voltage, and the current output terminal of the second adjustable current source is electrically connected to a fourth power supply voltage; 5. The amplifier of claim 4.

10. a first current buffer module connected in series between the transconductance amplifier module and the output terminal of the amplifier, the first current buffer module having a pair of first buffer control terminals for receiving a reference voltage; 10. The amplifier of claim 1.

11. a front-end module including an attenuation unit and the amplifier according to any one of claims 1 to 10, the input end of which is connected to the attenuation unit; a sampling module; an input module; a control processing module; a display module; and a storage module; oscilloscope.

12. a probe input terminal, a probe input resistor, a probe input capacitor, the amplifier according to any one of claims 1 to 10, whose input terminals are connected to the probe input resistor and the probe input capacitor, respectively, and a probe output terminal; Oscilloscope probe.

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